Connection for the control electrode of a semiconductor rectifier



Feb. 22, 1966 E. KELLER CONNECTION FOR THE CONTROL ELECTRODE OF A SEMICONDUCTOR RECTIFIER Filed Jan. 7, 1963 Eduard l fi e l BY M JWY P a/ United States Patent 3,237,063 CONNECTION FOR THE CONTROL ELECTRODE OF A SEMICONDUCTOR RECTIFIER Eduard Keller, Wettingen, Switzerland, assignor to Brown, Boveri & Company Limited, Baden, Switzerland, a joint-stock company Filed Jan. 7, 1963, Ser. No. 249,864 Claims priority, application Switzerland, Jan. 10, 1962,

266/62 2 Claims. (Cl. 317-234) The invention concerns an arrangement for establishing a .connection for the control electrode of a controllable semiconductor rectifier provided with a gas-tight casing and a connecting bolt which passes through the casing in an insulated manner.

The invention is characterized by the feature that the connecting bolt is provided with a bore which is shut off from the inside in a gas-tight manner by an insulation tube and a metal tube located on said first tube in the axial direction within the bore, and that inside the metal tube a connecting wire is soldered to it which is joined to the control electrode.

The invention is now explained with reference to a constructional example shown in section in the accompanying drawing. In the figure reference numeral 1 indicates a metallic part of the gas-tight casing in which the controllable semiconductor element 10 is located. The control spot or electrode on the active part of the semiconductor element to which control current is applied is indicated schematically by the dot 10a. The connecting bolt 3 is arranged above the ceramic tube 2 and the lower part of tube 2 is supported in an upstanding manner on the metallic base part 1 which is electrically conductive and is in contact with the lower surface of the semiconductor element 10.

The connection bolt 3 is provided with a bore 3a. An insulation tube 6 is fixed inside this bore by means of a solder joint 7 which makes a gas-tight connection. Inside the bore in the axial direction a metal tube 5 is mounted on the insulation tube 6 and connected to it in a gas-tight manner by means of a further solder joint 7a. Inside the metal tube at its upper end 5a a connecting wire 4 is soldered to the tube, this wire providing a connection through the center of the assembly to the control electrode spot 10a on the semiconductor element 10. A hollow stranded cable 8 surrounds the control current conductor 4 below connecting bolt 3 and is electrically connected at the opposite ends thereof to bolt 3 and to an annular plate 11, the latter being disposed on the upper surface of and being electrically connected to semiconductor element 10.

The metal tube 5, which is soldered at 5a to the upper end of conductor wire 4, serves as a contact pin for a plug socket not shown, which can be mounted on the connecting bolt 3. Prior to making the soldered joint 5a, tube 5 which is then open at its upper end, can be connected to a vacuum pump for evacuating the space within the ceramic tube 2 and casing part 1 in which the semiconductor element 10' is to operate.

What I claim is:

1. A controllable semiconductor rectifier assembly comprising a gas-tight casing including a lower metallic and electrically conductive base part and a tubular part of insulating material extending upwardly from said base part, a connecting bolt extending into said casing in a gas-tight manner, said connecting bolt having a longitudinally extending through bore, means electrically connecting the lower end of said connecting bolt with the upper surface of a semiconductor element of the controllable type supported within said casing, means electrically connecting the lower surface of said semiconductor element with said conductive base part, a tubular insulator located coaxially within the bore of said connecting bolt and having a coaxial electrically conductive tube, extending upwardly thereon, the interior of said tubular insulator and tube being in communication with the interior of said casing through the bore in said connecting bolt but being closed off to the outside in a gas-tight manner, and a conductor wire lo-- References Cited by the Examiner UNITED STATES PATENTS 2,827,597 3/1958 Lidow 317-234 2,981,873 4/ 19-61 Eannarino 317--234 3,025,435 3/ 1962 Green 174- 52 3,105,926 10/1963 Herlet 174-50.5 X 3,145,329 8/1964 Deskin et al 317-234 FOREIGN PATENTS 864,004 3/1961 Great Britain. 876,133 8/1961 Great Britain.

JOHN F. BURNS, Primary Examiner.

JOHN P. WILDMAN, E. JAMES SAX, Examiners. 

1. A CONTROLLABLE SEMICONDUCTOR RECTIFIER ASSEMBLY COMPRISING A GAS-TIGHT CASING INCLUDING A LOWER METALLIC AND ELECTRICALLY CONDUCTIVE BASE PART AND A TUBULAR PART OF INSULATING MATERIAL EXTENDING UPWARDLY FROM SAID BASE PART, A CONNECTING BOLT EXTENDING INTO SAID CASING IN A GAS-TIGHT MANNER, SAID CONNECTING BOLT HAVING A LONGITUDINALLY EXTENDING THROUGH BORE, MEANS ELECTRICALLY CONNECTING THE LOWER END OF SAID CONNECTING BOLT WITH THE UPPER SURFACE OF A SEMICONDUCTOR ELEMENT OF THE CONTROLLABLE TYPE SUPPORTED WITHIN SAID CASING, MEANS ELECTRICALLY CONNECTING THE LOWER SURFACE OF SAID SEMICONDUCTOR ELEMENT WITH SAID CONDUCTIVE BASE PART, A TUBULAR INSULATOR LOCATED COAXIALLY WITHIN THE BORE OF SAID CONNECTING BOLT AND HAVING A COAXIAL ELECTRICALLY CONDUCTIVE TUBE, EXTENDING UPWARDLY THEREON, THE INTERIOR OF SAID TUBULAR INSULATOR AND TUBE BEING IN COMMUNICATION WITH THE INTERIOR OF SAID CASING THROUGH THE BORE IN SAID CONNECTING BOLT BUT BEING CLOSED OFF TO THE OUTSIDE IN A GAS-TIGHT MANNER, AND A CONDUCTOR WIRE LOCATED WITHIN SAID TUBE AND ELECTRICALLY CONNECTED THERETO, SAID WIRE EXTENDING THROUGH SAID INSULATOR AND BEING CONNECTED TO THE CONTROL POINT ON SAID SEMICONDUCTOR ELEMENT. 